Crafted with precision, the outer protective layer of the Pre-Insulated Steel Pipe with HDPE Jacket and Polyurethane Foam for Thermal Insulation is formed from high-strength, high-toughness polyethylene material. Leveraging the groundbreaking polyethylene modification technology developed by Shandong Donghong Pipe Industry Co., Ltd., this layer undergoes a specialized surface polarization process. This state-of-the-art technique significantly enhances its adhesive compatibility with polyurethane, ensuring superior adhesion performance. The result is unmatched durability and unrivaled efficiency in thermal insulation applications, making this product the premier choice for robust, long-lasting underground steam piping solutions.
| Working Steel Pipe Diameter mm |
Outer Sheath Diameter mm |
Minimum thickness of outer sheath mm |
Insulation layer thickness mm |
| 426 |
494-554 |
4.0 |
30-60 |
| 478 |
547-607 |
4.5 |
30-60 |
| 529 |
598-658 |
4.5 |
30-60 |
| 630 |
700-760 |
5.0 |
30-60 |
| 720 |
790-850 |
5.0 |
30-60 |
| 820 |
891-951 |
5.5 |
30-60 |
| 920 |
992-1052 |
6.0 |
30-60 |
| 1020 |
1093-1153 |
6.5 |
30-60 |
| 1120 |
1194-1254 |
7.0 |
30-60 |
| 1220 |
1316-1436 |
8.0 |
40-100 |
| 1420 |
1538-1678 |
9.0 |
50-120 |
| 1620 |
1760-1880 |
10.0 |
60-120 |
| 1820 |
1960-2080 |
10.0 |
60-120 |
| Note: can be customized as customer's needs. |
1. Working Steel Pipe: Meticulously crafted from premium seamless steel pipe, spiral welded pipe, and straight seam welded pipe. Before thermal insulation, our pipes undergo rigorous mechanical rust removal to ensure a quality standard that meets or exceeds GB/T8923.1 Sa level 2.5. This guarantees unparalleled reliability and durability, making our pipes the gold standard in the industry.
2. SleePipe: Engineered with an exclusive blend of modified flame retardant and anti-static polyethylene resin, processed using state-of-the-art single screw extrusion technology. This results in pipes with exceptional impact resistance, superior isolation properties, and formidable corrosion resistance, perfectly suited for the most demanding applications.
3. Polyurethane Insulation Layer: We utilize cutting-edge, modified flame retardant polyurethane foam, injected under high pressure to fill the gap between the casing and the working steel pipe. This process ensures a superior insulation effect, characterized by exceptionally low thermal conductivity, high compression strength, minimal water absorption, and an impressive closure rate, guaranteeing optimal thermal performance.
1. Eliminates the need for additional support, significantly reduces heat loss, and completely eradicates the 'support thermal bridge' phenomenon, greatly enhancing energy efficiency.
2. Offers remarkable strength and excellent toughness, combined with ease of welding and convenient construction. This ensures seamless integration into any project, providing both efficiency and durability.
3. Exhibits exceptionally low thermal conductivity along with robust waterproof and corrosion resistance properties. Ideal for direct burial in the ground or underwater applications, providing unparalleled versatility and reliability.
4. Ensures straightforward connection through flange or quick joint connections, simplifying the installation process and significantly reducing labor costs.
5. Boasts an impressive service life, enduring challenging environments with temperatures ranging from -20ºC to 120ºC for over 30 years, thereby ensuring long-term performance and reliability.
Discover a diverse array of connection methods meticulously designed to amplify the efficiency and reliability of your operational processes.
| Flange connection |
Flexible socket connection |
Immerse yourself in a detailed welding joint demonstration that guarantees seamless integration, providing strong, durable, and long-lasting performance for all your needs.
Insulation steel pipes are indispensable in liquid and gas transmission pipe insulation projects across various sectors such as petroleum, chemical industries, central heating systems, heating networks, central air-conditioning ventilation pipes, and municipal engineering. Our high-temperature prefabricated direct-buried thermal insulation steel pipe stands out as a premier choice, offering exceptional thermal insulation performance, unparalleled safety and reliability, and notably reduced construction costs. Specifically designed to excel in the most demanding conditions, these pipes ensure longevity and efficiency, making them an invaluable asset for industrial and municipal applications alike. By choosing our solution, you are making a wise investment in cutting-edge technology, superior engineering, and sustainable infrastructure.
Shandong Donghong Pipe Industry Co., Ltd. (stock code: 603856), or Donghong Co., Ltd., proudly operates out of Qufu, China, the historical birthplace of Confucius. As a pioneering force in the engineering pipeline sector, we distinguish ourselves as a leading manufacturer, comprehensive service provider, and general contractor. Our core expertise encompasses four crucial segments of customized pipeline solutions: rainwater and sewage diversion, municipal services, industrial and mining sectors, and major national engineering projects. At Donghong Co., Ltd., we are dedicated to fostering a dynamic industrial ecosystem, integrating design institutes, financial institutions, port logistics, construction firms, and an extensive network of upstream and downstream enterprises. Our forward-thinking approach aims to reshape the global pipeline industry. Our mission is to lead with intelligent pipeline solutions that enhance quality of life and ensure the enduring safety of pipeline transportation.
Donghong Co., Ltd. is proud to employ a dynamic team of over 200 R&D experts and boasts an impressive portfolio of over 100 patents. Our innovation is driven by national technology platforms, including our enterprise technology center, CNAS laboratory, academician expert workstation, and post-doctoral workstation. We are at the cutting edge of digitalizing, informatizing, and intelligentizing pipeline engineering, driving the industry forward and setting new standards of excellence.
In November 2017, Donghong Co., Ltd. achieved a significant milestone by becoming the first company in China's engineered composite piping systems sector to be listed on the main board of Shanghai.
Outstanding Technical Research and Development Capabilities
Our state-of-the-art national CNAS laboratory is outfitted with the latest testing technologies, enabling the innovation of new products, materials, and connection types. This rigorous testing ensures that our products consistently maintain stability and reliability, reflecting our steadfast commitment to excellence.
Donghong has forged exclusive strategic alliances with over five premier 5A-level logistics companies, renowned for their extensive transportation expertise. By seamlessly integrating automobile, railway, port, and maritime logistics, we deliver exceptional service even in the most extreme temperatures and remote locations. Our comprehensive transportation network ensures that your order reaches its destination promptly, maintaining the pinnacle of efficiency and reliability. Our meticulous packaging and shipping processes protect the integrity and quality of our Pre-Insulated Steel Pipe with HDPE Jacket and Polyurethane Foam, ensuring they are primed for immediate installation upon arrival. Experience the ultimate in convenience and peace of mind with Donghong's unrivaled logistics solutions.
1. Does your product meet international standards?
Our products not only excel in passing CE, BV, ISO, and WAR certifications but also surpass all necessary standards. Let us know your required national standard, and we will verify or test it to ensure compliance, delivering unmatched quality and reliability.
2. What kinds of services do you offer?
As an industry leader, we provide a comprehensive range of pipe products, fittings, packaging, and seamless shipping solutions. Our consultancy services offer expert project consulting, cutting-edge pipe system solutions, and detailed design recommendations. Furthermore, our engineering expertise enables us to excel in pipeline contracting, repair services, and free maintenance guidance, ensuring complete support for all your needs.
3. Do you support OEM/ODM services?
Absolutely, we provide extensive customization options in materials, specifications, logos, packaging, and connection methods. Our expert team excels in delivering bespoke solutions tailored to your specific projects, demonstrated by numerous successful cases that showcase our exceptional service.
4. What are your terms of payment?
We accept T/T (Telegraphic Transfer) and L/C (Letter of Credit) at sight, offering you flexibility and convenience in payment options.
5. How can you guarantee the quality of your goods?
We warmly welcome all customers to visit our company and inspect our products firsthand. Additionally, we can conduct rigorous tests upon your request before the order. We also offer sample testing before bulk production to ensure the highest quality standards are met for your complete satisfaction.
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